CVE-2018-1000637

zutils version prior to version 1.8-pre2 contains a Buffer Overflow vulnerability in zcat that can result in Potential denial of service or arbitrary code execution. This attack appear to be exploitable via the victim openning a crafted compressed file. This vulnerability appears to have been fixed in 1.8-pre2.

Published: 2018-08-20 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2018-1000637 is rated Moderate Risk (58.3/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.68%). EPSS rose +1.28% over the last day, indicating growing attacker interest. Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2018-1000637

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.40% 1.68% +1.28%
2 2025-07-21 0.46% 0.40% -0.06%
3 2025-03-30 — 0.46% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-1000637

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.0 HIGH
CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 5.9 [email protected]
6.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.6 6.4 [email protected]

Weakness enumeration for CVE-2018-1000637

OS Trackers for CVE-2018-1000637

vendor priority summary link
debian not yet assigned CVE-2018-1000637 not yet assigned priority: Debian including 1 source packages (zutils), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2018-1000637
ubuntu medium CVE-2018-1000637 medium priority: Ubuntu including 1 source packages (zutils), 19 status rows across 19 suites (bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 15, needed 2, DNE 1, released 1. https://ubuntu.com/security/CVE-2018-1000637

Affected software / configurations for CVE-2018-1000637

Vendor Product Version Raw CPE
nongnu zutils <= 1.8 cpe:2.3:a:nongnu:zutils:*:*:*:*:*:*:*:*
nongnu zutils 1.8 cpe:2.3:a:nongnu:zutils:1.8:pre1:*:*:*:*:*:*
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*

References for CVE-2018-1000637

URL Tags
https://bugs.debian.org/904819 Issue Tracking Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2018/09/msg00016.html Mailing List Third Party Advisory
https://lists.nongnu.org/archive/html/zutils-bug/2018-08/msg00000.html Mailing List Third Party Advisory
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